Bottom bar organization for venetian blinds



Nov. 17, 1953 H. K. LORENTZEN BOTTOM BAR ORGANIZATION FOR VENETIAN BLINDS FIG.4-

Filed Feb. 4, 1950 INVENTOR mm A. 10 m TZl-W HIS ATTORNEYS Fatentecl Nov. 17, 1953 BOTTOM BAR ORGANIZATION FOR VENETIAN BLINDS Hans K. Lorentzen,

Montclair, N. J., assignor to Lorentzen Hardware Mf Corp., New York, N. Y., a corporation of New York Application February 4, 1950, Serial No. 142,492 2 Claims. (01. 160-173) This invention relates to Venetian blinds, and more particularly to a bottom bar organization.

Venetian blinds are customarily provided with a bottom bar extending for the width of the blind and to which the lower ends of the ladder tapes and the lift cords are attached. This bar is usually thicker and heavier than the intermediate slats the blind.

in the form shown of the present invention, the bottom bar is formed of an assembly of rolled and stamped sheet metal parts consisting principally of an open-topped channel, a resilient, transversely arched sheet metal cover for closing the open side of the channel, fittings for securing the ends of the ladder tapes and lift cords to the bottom bar, and cap members to close the ends of the channel. This invention is in some respects an improvement over that shown in my copending application S. N. 5,487, filed September 13, 1949.

Among the objects of the present invention are to provide a Venetian blind bottom bar organization of pleasing appearance which can be rapidly and economically manufactured on a quantity production basis, which can readily be assembled to, or disassembled from, a Venetian blind without the use of tools, and to generally improve metal bottom bar organizations for Venetian blinds.

My invention is clearly defined in the appended claims. In the claims, as well as in the description, parts may at times be identified by specific names for clarity and convenience, but such nomenclature is to be understood as having the broadest meaning consistent with the context and with the concept of my invention as distinguished from the pertinent prior art. The best form in which I have contemplated applying my invention is illustrated in the accompanying drawings forming part or this specification, in which:

Fig, 1 is a front elevation of a Venetian blind embodying the bottom bar organization of the present invention.

Fig. 2 is a perspective of the bottom bar per se, parts being broken away to show details of construction.

Fig. 3 is a vertical section taken generally on the line 2-3-3 of Fig. 2.

Fig. l is a vertical section similar to Fig. 3, certain parts being in exploded relation to facilitate explanation of the assembly procedure.

Fig. 5 is a perspective of the fitting, viewed from the bottom.

Fig. 6 is a perspective of a modified form of the fitting.

Reference will now be had to the drawings, in which the same reference numerals will refer to the same parts throughout the several views. A rolled sheet metal channel it extends along the bottom of a Venetian blind H. A pair of duplicate fittings, designated as a whole by H (one shown), is secured to the channel by snap engagement therewith. The lower ends of the vertical branches 54, i l of ladder tapes, designated as a whole i5, iii, are secured to the fittings. An enlarged lift cord end it is also secured to each fitting 52. This enlargement may be formed in any suitable manner, as by clam ing a bead on the cord, as more fully explained in my application 8. N. 115,407, filed September 13, 1949'. A slat, serving as an arched cover member ll, is positioned on top of the channel; and a cap member ii is telcscoped over each end of the channel and the adjacent end or" the cover, thereby securing the cover ll to the channel ill.

The channel is may be a length out from rolled sheet metal stock of indeterminate length, the channel is ordinarily being of the same length as the slats it of the blind. rhe channel it has parallel spaced vertical side walls 25, 29, the top portions of the channel walls being turned inwardly and formed into confronting flanges t l 2i that are inclined slightly upwardly. The flanges 2i, 25 extend throughout the length of the channel. Pairs of short longitudinal portions 22, 22 of the flanges 2!, ii on the two sides of the channel it are depressed below the general level of the flanges 2 l, 25 (see Fig. 2 and Fig. 4.) Metal is pressed upwardi from the bottom of the channel it? to form parallel beads 28 that extend longitudinally for the length of the channel. These beads increase the rigidity of the channel.

Each of the fittings i2 is attached to the Venc tian blind H by securing thereto the lower ends of the vertical branches it, i l of one of the lad-" der tapes It, IS and an enlarged lift cord end it. Each fitting i2 is a generally rectangular arched sheet-metal stamping, which includes an arched rectangular plate 2c adapted to span across the channel ill.

Central side portions of the plate are elevated so as to form inclined lips si, ill. The lips 3!, 3t are so arranged that when each fitting i2 is secured to the channel ill, the lips 3i will overlie and be spaced from the depressed portions 22, 22 of the channel, see Fig. 3. Space is thereby provided between the fitting portions El, 35 and the depressed portionsEZ, 22 of the flanges 25, 2|

of the channel for the passage of the vertical branches I4, ll of a ladder tape. The lips 3|, 3| of each fitting l2 terminate in such spaced relation as to spread the two vertical branches |4, H of the ladder tape I by an amount equal to the overall width of the channel I, which is equal to the width of the blind slats. This is the proper spaced relationship for the two vertical branches of the ladder tape (see Figs. 3 and 4) to enable the cover member I! of the bottom bar to lie flat against the flanges 2|, 2|. Thus the lips 3|, 3| of the fitting |2 prevent a tensioned ladder tape from exerting force on the cover member I! which would tend to tilt or displace the same.

An extension 32, adjacent each of the four corners of the plate 24, projects downwardly and inwardly (see Figs. 3 and 4). Each extension 32 is formed with a resilient nose portion 35. Bridge members 34, 34 (Fig. 5) integrally connect each pair of extensions 32, 32 that lie on the same side of the fitting l2; and these bridge members 34, 34 are adapted to receive and have secured thereon the ends of the vertical branches |4, H of a ladder tape l5. Upon complete assembly, each vertical branch of the ladder tape will extend down past the inclined lip 3| of the fitting |2, through the space between the inclined lip portion 3| and the downwardly-depressed portion 22 of the flange 2|, and thence between the extensions 32, 32 on that side of the fitting |2. The end of the ladder tape branch I4 is folded about the bridge member 34. A resilient U- shaped clip 36 is then telescoped over that portion of the ladder tape that is folded about the bridge member, thereby clamping the ladder tape branch to the bridge member. If desired, other means, such as stapling, may be used to secure the ends of the vertical branches of ladder tapes looped around the respective bridge members 34.

A center portion 28 may be embossed upward and provided with a keyhole slot 25. However, if desired the embossing of the center portion 23 may be omitted, and the slot located in the arched plate 24, see Fig. 6. In either case, a small end 26 of the slot 25 is centrally located in the plate 24. An enlarged lift cord end H5 is insertable through the large end 29 of the keyhole slot 25. The lift cord 33 is then shifted through a narrow passage 33 to the small end 2c of the keyhole slot. The passage 33 is preferably slightly narrower than the nominal diameter of the cord 30, so that the edges of the slot will squeeze the cord slightly as the cord is pushed sidewise to shift enlargement Hi to the small end 23 of the keyhole slot. This relationship of slot width and cord size prevents accidental return of the cord to the big end of the keyhole slot, and thereby prevents the cord from being fortuitously disengaged from fitting |2. The fittings |2, |2 in some respects are similar to the fittings disclosed in my copending application S. N. 115,407 filed September 13, 1949.

The ladder tapes having been secured to the fittings |2, |2 as previously described, the slats are put in place in the ladder tapes. The bottom slat, which is to act as the cover member H for the bottom bar, is placed on top of the fittings |2, |2. The center embossed portion 28 together with the lips 3|, 3| form an arch which aids in supporting the cover member IT. The lift cords are then reeved through the openings in the various slats including the openings 4| (one shown) in the cover member H. The ends of the lift cords are then secured in the keyhole slots II as previously described.

' tion is one composed of but few With the ladder tapes and lift cords secured to the fittings |2, |2, the next step in the assembly is the securing of the fittings to the channel H). The fittings |2, |2 are positioned on the top of the channel with the inclined lip portions 3|, 3| thereof overlying the depressed portions 22, 22 of the channel flanges 2|, 2|. The fittings are then pressed downwardly, the four resilient nose portions 35 of each fitting making snap engagement with the edge of a channel flange 2| adjacent one end of a depressed portion 22. By bending the extensions 32, 32 to decrease or increase the distance between the nose portions 35, 35 which are on opposite sides of the bottom bar, a looser or tighter fit may be obtained.

With the fittings secured to the channel, the ladder tapes are further secured against any for tuitous disengagement, since each vertical branch |4, after extending down past the edge 43 (see Fig. 5) of the inclined lip portion 3| of the fitting, turns inwardly between the inclined lip portion 3| and the adjacent depressed portion 22 of the flange. After the fitting has been secured, the vertical branches of the ladder tape are held taut below the fitting, as can be seen by comparing Figs. 3 and 4.

Cap members l9, l9 which may be molded from plastic in one piece, are telescoped over the ends of the channel These cap members embrace the edjacent end portions of the cover member and thereby secure the cover member to the channel l3.

It will be seen that this bottom bar organizaparts which may be rapidly and economically manufactured, and that the bar organization is one which can be assembled in a facile manner without the use of special tools.

The bottom bar herein disclosed has the necessary rigidity to act as a carrier for the slats on the raising of the blind, and the ladder tapes and lift cords are attached to the channel, via the fittings, in such manner that they will not be disengaged upon the sudden arresting of the bottom bar when the blind is lowered rapidly.

What I claim is:

1. In a Venetian blind, a bottom bar organization comprising: a sheet metal channel extending along the bottom of the blind, the top portions of the channel walls being turned inwardly and formed into confronting flanges that extend throughout the length of the channel, pairs of short longitudinal portions of the flanges on the two sides of the channel being depressed below the general level of the flanges; arched sheet metal fittings spanning the space between the side walls of the channel, one fitting being positioned on top of each of said pairs of depressed flange portions and each fitting having portions making snap engagement with non-depressed portions of said flanges; a lift cord attached to each of said fittings; a vertical ladder tape branch passing around each longitudinal edge of each of said fittings and being secured to the fitting on the under side thereof; and a single cover member overlying said fittings and said confronting flanges of the channel.

2. In a Venetian blind, a bottom bar organization comprising: a sheet metal channel extending along the bottom of the blind, the top portions of the channel walls being turned inwardly and formed into confronting flanges, pairs of short longitudinal portions of the flanges on the two sides of the channel being depressed below the general level of the flanges; arched sheet metal fittings spanning the space between the side References Cited in the file of this patent Walls of the channel one fitting being positioned UNITED STATES PATENTS on top of each of said pairs of depressed flange portions and each fitting having portions mak- Number Name Date ing snap engagement with said confronting 5 2 gg g gf g 2g flan es; a vertical ladde ta e branch assi 1 1 g r p p ng 2,402,894 Jablin June 25, 1946 around each longitudinal edge of each of said fittings and being secured to the fitting on the 2485,21? Semflof 1949 under side thereof; and a single cover member 21502928 Rosenbaum 23, 1950 overlying said fittings and said confronting m 508,742 Ben May 1950 flanges of t channeL 2,529,229 Sherwood NOV. 7, 1950 HANS K. LORENTZEN. 

